External Potentiometer

[mbsteed]

We have a 3 axis gimbal and wondered about the need for an external potentiometer. We will be using Savox 1258 modified for 360 degrees. We plan to use the Hover-fly gimbal controller. Do we need to use a potentiometer if we are using the gimbal controller to stabilize the camera? Confused.

 

[mbsteed]

...so no need for an external potentiometer? Logically I don't see the difference between an internal and an external one (those are both going to be moving relative to the other so .... what is the point?

 

[Efliernz]

The external pot is great if you are modifying the servo for continuous rotation with reduction belts/gears. The internal pot is only good for 270 deg of servo rotation. If you have a 5:1 belt/gear reduction from servo to tilt, for the mount to tilt 90 deg down, the servo needs to rotate 4 x 90=450 degrees. If you move the pot onto the tilt axis for position feedback, you get a much better resolution and smoother movement.

I hope that helps

Some gimbal controllers dont use the feedback pot (like Skyline). They use a set 2.4K:2.4K resister to simulate the pot sitting in the middle the whole time. It alters the servo signal to make it move to the wanted position.

Pete

 

[mbsteed]

Efliernz,

Thanks for the information - that makes so much more sense now. Great information. I think in our case, we will setup the Hoverfly gimbal on the camera plate so that will probably be redundant with the potentiometer.